Refine
Has Fulltext
- no (2)
Year of publication
- 2016 (2)
Language
- English (2)
Is part of the Bibliography
- yes (2) (remove)
Keywords
- Epigenetics (2) (remove)
Institute
The concept of developmental origins of diseases has gained a huge interest in recent years and is a constantly emerging scientific field. First observations hereof originated from epidemiological studies, linking impaired birth outcomes to adult chronic, noncommunicable disease. By now there is a considerable amount of both epidemiological and experimental evidence highlighting the impact of early life events on later life disease susceptibility. Albeit far from being completely understood, more recent studies managed to elucidate underlying mechanisms, with epigenetics having become almost synonymous with developmental programming. The aim of this review was to give a comprehensive overview of various aspects and mechanisms of developmental origins of diseases. Starting from initial research foci mainly centered on a nutritionally impaired intrauterine environment, more recent findings such as postnatal nutrition, preterm birth, paternal programming and putative interventional approaches are summarized. The review outlines general underlying mechanisms and particularly discusses mechanistic explanations for sexual dimorphism in developmental programming. Furthermore, novel hypotheses are presented emphasizing a non-mendelian impact of parental genes on the offspring's phenotype.
Maternal environmental factors can impact on the phenotype of the offspring via the induction of epigenetic adaptive mechanisms. The advanced fetal programming hypothesis proposes that maternal genetic variants may influence the offspring's phenotype indirectly via epigenetic modification, despite the absence of a primary genetic defect. To test this hypothesis, heterozygous female eNOS knockout mice and wild type mice were bred with male wild type mice. We then assessed the impact of maternal eNOS deficiency on the liver phenotype of wild type offspring. Birth weight of male wild type offspring born to female heterozygous eNOS knockout mice was reduced compared to offspring of wild type mice. Moreover, the offspring displayed a sex specific liver phenotype, with an increased liver weight, due to steatosis. This was accompanied by sex specific differences in expression and DNA methylation of distinct genes. Liver global DNA methylation was significantly enhanced in both male and female offspring. Also, hepatic parameters of carbohydrate metabolism were reduced in male and female offspring. In addition, male mice displayed reductions in various amino acids in the liver. Maternal genetic alterations, such as partial deletion of the eNOS gene, can affect liver metabolism of wild type offspring without transmission of the intrinsic defect. This occurs in a sex specific way, with more detrimental effects in females. This finding demonstrates that a maternal genetic defect can epigenetically alter the phenotype of the offspring, without inheritance of the defect itself. Importantly, these acquired epigenetic phenotypic changes can persist into adulthood.